Combination motor grader and bulldozer



April 3, 1962 Filed July 25, 1958 E. R. CUNNINGHAM, JR

COMBINATION MOTOR GRADER AND BULLDOZER 3 Sheets-Sheet 1 INVENTOR.

ERNEST R CUNNINGHAM JR LIN D BERG & BRADWAY ATTO RN EYS April 3, 1962 E. R. CUNNINGHAM, JR ,5

COMBINATION MOTOR GRADER AND BULLDQZER 5 Sheets-Sheet 2 Filed July 25, 1958 INVENTOR. E RNEST R. CUNNINGHAM JR.

Ll NDBERG 8. BRADWAY ATTORNEYS April 3, 1962 E. R. CUNNINGHAM, JR

COMBINATION MOTOR GRADER AND BULLDOZER 5 Sheets-Sheet I5 Filed July 25, 1958 INVENTOR. ERNEST R, CUNNINGHAM JR LINDBERG 8 BRADWAY AT TO RN EYS anchored to the tractor frame.

3,027,662 COMBINATION MOTOR GRADER AND BULLDOZER Ernest R. Cunningham, .lr., P.0. Box 566, Lihertyville, Ill.

Filed July 25, 1958, Ser. No. 751,005 14 Claims. (Cl. 37180) This invention relates generally to grading equipment, and particularly to improved equipment which can readily be modified for operation as either a patrol grader or a bulldozer. It may also be modified for use as a portable crane.

The improved machine according to the present invention preferably makes use of a wheeled tractor affording a mounting for a pivot frame supporting a boom having a caster wheel at the forward end thereof in contact with the grade surface. The pivot frame supports essentially vertical gimbal mounted hydraulic cylinders, each being connected near the outer end of a dozer blade. Such dozer blade preferably consists of two connected portions which are raised and lowered by the aforesaid gimbal mounted cylinders. The ends of the each half dozer blade are moved in a horizontal plane by means of hydraulic cylinders having one end The dozer blade is prevented from rocking about its longitudinal axis by telescoping members extending in the same general direction as the last named hydraulic cylinders, each telescoping member being connected to a link extending from a point near the outer end of the dozer blade portion and to a point at the last named cylinder. The links have a moment taking connection to the blade portion, and the connection of the telescoping members to the links is likewise capable of taking moment, so as to maintain the blade portion in the desired attitude.

Each inner end of the dozer blade portions is connected to a hydraulic cylinder also connected to the tractor frame, and these cylinders cooperate with the gimbal mounted cylinders and the other cylinders previously mentioned to maintain the dozer blade portions in the conventional positon for blade grading, or in a position at various angles to the tractor frame for angle grading. By reason of the last described hydraulic cylinders, the blade portions can be positioned so as to describe a V for plowing, or as a V of opposite sense to cause the blades to act as" an open bottomed load carrying scraper. It is possible also to move the blade endwise of itself with respect to the tractor frame, so that grading can be carried on at one side or the other of the tractor.

When the boom is removed, the pivot or tilting frame is locked to the tractor frame, and the gimbal mounted cylinders as well as the other cylinders connected between the blade portions and the tractor frame can operate as described above, and the machine not only has the function previously described of a patrol grader, but also the additional functions of a dozer.

The boom can be extended or contracted as desired, and it can also be raised or lowered as a crane boom, with or without the caster wheel, for the placing of underground pipe, poles, as desired.

With the foregoing considerations in mind it is a principal object of this invention to provide an improved grading machine, capable of selective operation either as a motor patrol grader or as a bulldozer.

Another object is to provide a grading machine where the blade is comprised of two portions which can be positioned as desired both in vertical and horizontal directions.

Still another object is to provide a machine of the class described for operation either as a patrol grader aren't or as a dozer, the blade being capable of being oriented to selected positions whether the operation is as a patrol grader or as a dozer.

Yet another object is to provide linkages acting between the tractor frame and a frame capable of movement with respect to the tractor frame, such linkages enabling a dozer blade consisting of half portions to be oriented to any desired position.

A still further object is to provide an improved dozer having blade portions movable to selected positions by linkages acting between the tractor frame and an auxiliary frame capable of being locked in position with respect to the tractor frame.

A further and important object is to provide a dozer blade which can be moved laterally of itself with respect to the tractor frame, the blade being also capable of angular positioning as well as movement endwise of itself for grading to one side of the tractor.

Other objects and important features of the inven tion will be apparent from a study of the specification following taken with the drawings which together describe and illustrate a preferred embodiment of the invention and what is now considered the best mode of practicing the principles thereof. Other embodiments may be suggested to those having the benefit of the teachings herein, and such other embodiments are intended to be reserved especially as they fall within the scope and spirit of the subjoined claims.

-In the drawings:

FIG. 1 is an elevation view of a combination patrol grader and dozer according to the present invention;

FIG. 2 is a plan veiw thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a section taken substantially along the line 44 of FIG. 2 looking in the direction of the arrows;

FIG. 5 is a longitudinal sectional view of the telescoping member seen in FIG. 4;

FIG. 6 is a view along the line 66 of FIG. 3 looking in the direction of the arrows, showing details of a center post connecting the grader blade wing portions seen in FIGS. 1, 2 and 3;

FIG. 7 is a section taken along the line 7-7 of FIG. 6 looking in the direction of the arrows, certain parts being shown in elevation, showing details of the center post and mounting for a center blade portion of the grader blade seen in FIGS. 1 to 3, inclusive;

FIG. 8 is a section taken substantially along the line 8-8 of FIG. 6 looking in the direction of the arrows, showing how the center blade portion bears against the wing portions seen in FIGS. 1 to 3;

FIG. 9 is a plan view showing how the grader blade consisting of the wing portions and the center portion can be placed in a straightaway canted position for angle dozing or grading;

FIG. 10 is a plan 'view showing how the wing portions of the blade can be positioned to provide a V-configuration wherebythe blade portions can operate as an open-bottomed load carrying scraper;

HS. 11 is a view similar to FIG. 9, but showing the blade in a straightaway position of an opposite sense from that seen in FIG. 9, the position shown being also for angle dozing or grading; and

FIG. 12 is a view showing how the blade portions can be positioned to form a V of opposite sense from that seen in FIG. 10, so that the dozer blade portions can operate as a plow.

Referring now particularly to FIGS. 1 to 3 or" the drawings, the improved grader and dozer according to the present invention is referred generally by the reference numeral 20, and includes a wheeled tractor 21 having paired wheels 22 and 23. The wheels support a tractor frame 24, the tractor frame 24 in turn supporting an engine housing 26 enclosing a prime mover (not shown) for driving the tractor 21. The wheels 22 and 23 may be powered dirigible wheels, and alternately one pair of wheels may be powered and the other pair merely dirigible. It is also contemplated that the tractor be of the type where steering is accomplished by differential brakingof the wheels.

The tractor shown may also be of the crawler tread type without departing from the spirit of the invention.

The tractor frame 24 is also provided with an operators seat 27, there being a control point 28 disposed adjacent the operators seat 27, said control point sup porting one or more controls 29 for operating various elements of the grader and dozer.

As shown in FIG. 1, the grader 20 is shown for operation as a motor patrol grader. Irrespective of whether it is operated as a motor patrol grader or as a dozer, it is'provided with a tilting or pivot frame 31, pivoted at 32 to the front end of the tractor frame 24. As seen in FIGS. 1 and 2, the pivot frame 31 has rigidly secured thereto a boom element 33 which supports telescoping boom elements 34, 36 and 37 to provide a boom 35. Pin connections, such as shown at 38, maintain the boom elements in their proper locked-up relationship. Pins 38 may be; removed to shorten the boom 35, or the ele ments 34, 36 and 37 can be separated from boom element 33. The frontmost boom element 37 supports a caster wheel 39 turning about an axle 41 supported in swivel arms 42, swivel arms 42 turning in a horizontal plane upon a vertical bearing 43 at the forward end of the boom portion37.

The boom portion 37 has a plate 44 welded thereto, the plate having an' eye 46 for supporting any suitable kind of lifting device when the boom is raised under conditions as will be described.

The boom 35 together with its ground engaging wheel 39 cooperates with hydraulic cylinders 47, each of which has a gimbal mounting 48 to the pivot frame 31. Each cylinder 47 has a piston rod 49 which has a ball and socket connection 51, see also FIG. 4, to an upper lug 52 welded tothe rear face of a grader blade wing portion 53. A pair of link arms 54, 54 are held between the upper lug 52 and a lower lug 56 also welded to the rear face of the blade portion 53..

The link arms 54 are spaced by a bearing sleeve 57, and a pintle pin 58 is supported within the sleeve 57 and is anchored at its ends to the upper lug 52 and the lower lug 56. The other end of the link arms 54 is connected to a fluid motor shown as an hydraulic cylinder 59, see also FIG. 2, piston 61 thereof having a ball and socket connection 62 thereat.

Any tendency of the blade 53 to turn about its longitudinal axis is prevented by a cylindrical tube 63 welded at 64 to the upper and lower links 54. The tube 63 telescopes with a tube 66 of smaller diameter having a spherical bearing connection 68 at the end thereof remote from the blade 53, the connection 68 being to an abutment 69 supported by the tractor frame 24. A

In lieu of the telescoping cylindrical tubes 63 and 66 the telescoping members may be of rectangular cross section if desired.

The position of the outer ends of the blade portions 53 with respect to the tractor frame 24 can be adjusted by the cylinders 59 which have a spherical bearing connection 71 to the abutment 69. Since the connection of the cylindrical tube 63 to the links 54 is a rigid one, operation of the hydraulic cylinders 59 will determine the position of'the outer ends of the blade portions 53.

The inner ends of the blade portions 53 can be adjusted in their position with respect to the tractor frame 24 by means of'fluid motors in the form of hydraulic cylinders 72, one end of each cylinder 72 having a ball and socket connection 73 to a bracket 74 extending inward from the tractor-frame 24, The piston rod end 'of'each cylinder 72 has 'aball and socketconnection 76 with an upper bracket 77 turning freely on a central mounting post 78, see FIGS. 6 and 7. The brackets 77 are also welded to the rear face of the blade portion 53, and similar lower brackets 79 are also welded to the inner ends of the dozer blade. A bump pad 81 is secured by a pin 82 to the center post 78.

It will be seen that the outer ends of the blade portions 53 determine the angular position of the blade portions with respect to the frame 24. The cylinders 72 are connected to the inner end of the blade portions 53 at the laterally spaced brackets 74 on the main frame 24, and are selectively operated to determine the position of the inner ends of the blade. The connection of the cylinders 72 at the inner ends of the blade portions 53, and their connection to spaced points on the frame 24 constitute a three bar linkage which is a stable one geometrically.

Since the cylinders 72 provide means for changing the length of two of the sides of the three bar linkage, it will be seen that the inner ends of the blade portions 53 can be selectively positioned with respect to the frame.

For example, both cylinders 72 can be extended which will move the inner ends away from the frame 24, and if the cylinders 59 are retracted the blade portions 53 will adopt a position corresponding to a V-grader as seen in FIG. 12. Retraction of cylinders 72 and extension of cylinders 59 will give a position of the blade portions 53 as seen in FIG. 10.

Likewise, if one of the cylinders 72' is extended and the other contracted, the inner ends of the blade portions 53 will be shifted laterally of the frame 24, such positioning being indicated for grading to one side of the machine, if desired.

The two blade portions 53 would normally leavean opening therebetween, either when in the straightaway position as seen in FIGS. 9 and 11 or when in the V position seen in FIG. 12, except for the provisions of a spring loaded center section 83, see again FIG. 6. The center section 83 is formed from a curved plate having its upper end provided with bent down cars 84, 86 and 87. The bent down ear portions 84 and 86 are held pivotally to center post '78 by a pin 88 which passes through the upper part of the center post 78.

The center section 83 is urged against the blade portions 53 by a spring 89 having one end thereof bottomed against the underside of center section 83 at the top thereof, its other end being bottomed against a seat 91 on the bump pad 81. The movement of the center section to the right as seen in FIG. 6 is limited by a stop on the bump pad 81.

The lower edge of the center section 83 has a cutting edge 92 with beveled edges 93, see FIG. 8, and the thrusts against the center section 83 and its cutting edge 92 causes the same to come into firm contact with the blade portions 53 when the blades are in the position seen in FIGS. 9 and 11. However, when the blades 53 are oriented to the position seen in FIG. 10, the cutting edge 92 can ride up over the blade portions 53 so as to close the bottom of the V and thereby prevent spillage between blade portions 53.

The operation of themechanism thus far described is as follows:

The gimbal mounted cylinders 47 together with the cylinders 59 and 72 can be adjusted so that the grader blade consisting of the wing portions 53 and the center portion 83 is in the straightaway position as seen in FIGS. 1 and 3. The cylinders 59 and 72 merely adjust the positions of the blade portions 53 in a horizontal plane and with respect to the tractor frame 24, while the gimbal mounted cylinders 47 adjust the'position of the blade portions 53 and center portion 83 in a vertical plane. For ordinary gradingoperation the portions 53, 53'and 83 are in the same horizontal plane either in the positionat right angles to the longitudinal'axis of the grader 20, or in'positions as'seen in FIGS: 9 and 11-forangle'grading.

The gimbal mounted cylinders 47 can position the entire blade with one end raised higher than the other for sloping if desired.

As seen in FIGS. 1 and 2, the caster wheel 39 and its supporting boom 35 are held in position relative to the blade portions 53, since all of the cylinders would be in a condition with fluid trapped therein. But the entire assembly can move in a vertical plane by reason of the pivotal mounting 32 for the pivot frame 31. Large variations in the condition of the grade at the caster wheel 39 will reflect but small changes in vertical position of the blade portions 53 and 83, so that the same essential grade will be had as that over which the wheels 22 and 23 operate.

Under other conditions of grading it may be desirable to retract the inner ends of the wing portions 53 toward tractor frame 24 while the outer ends are extended away from the tractor frame to give a V configuration to the blade portions as seen in FIG. 10. Such may be indicated where it is desired to have grader 20 act as an open-bottomed scraper.

The apparatus thus far described can also be operated as a dozer at which time the boom 35 is removed or fully retracted. The pivot or tilting frame 31 is then rocked about the pivot 32 and is anchored to the tractor frame 24 by means of a'pair of pins 94 passing through an aperture 96 in an abutment member 97 on the tractor frame 24 and also through an aperture 98 in the tilting frame 3-1.

As before, the gimbal mounted cylinders 47 can raise and lower the blade portions 53 in a vertical plane, their position in a horizontal plane being adjusted by the cylinders 59 and 72. For operation as a dozer, the blade can be positioned as seen in FIGS. 9 to 12 inclusive, as well as the positioning seen in FIGS. 1 to 3.

The apparatus thus far described can also be operated as a crane with the blade portions 53 out of contact with the ground. The upper link 54 has an car 99 with an aperture ltil therein, and when the blade portions 53 are raised by the gimbal mounted cylinders 47, the aperture 101 can be aligned with an aperture 102 in a bracket 103 secured to the tractor frame 24, a pin passing through the two apertures 101 and 102 to maintain the blade portions 53 and 83 in an elevated position above the ground.

During operation as a crane it may be desirable to turn the boom portion 37 through 180 and to mount a suitable lifting device at the plate 44 and the opening 46 therein. It will be apparent that the entire vehicle may be freely manuevered as a crane with the blade out of contact with the ground, and the so-locked blade becomes an abutment for the operation of the gimbal mounted cylinders 47 to pivot the tilting frame 31 about its axis 32 to raise the boom 35 and lower it.

From the description foregoing, it is believed evident that there has been provided a new and improved combination motor grader and dozer. While the apparatus has been described in terms of a preferred embodiment thereof, its scope is intended to be limited only by the claims here appended.

I claim as my invention:

1. In a grading machine, a main frame having ground engaging elements, a grader blade comprising wing portions pivotally connected at the inner ends thereof, means for adjusting the inner and outer ends of said wing portions in a horizontal plane comprising an adjustable three bar linkage connected between the inner ends of said wing portions and said main frame, means connected between each wing portion and said main frame for adjusting the outer end of said wing portion, and means acting between said main frame and said wing portions for adjusting the position of said wing portions vertically.

2. In a grading machine, a main frame having ground engaging elements, a dozer blade including hingedly connected wing portions, fluid motor means connected between the inner end of each wing portion and said main frame for adjusting the position of the inner ends of said wing portions in a horizontal plane, said fluid motor means and the spacing of their connections to said main frame defining a selectively adjustable three bar linkage, additional fluid motor means connected between each wing portion at a point remote from the inner end thereof and said main frame for adjusting the position of the outer end of said wing portion in a horizontal plane, and means acting between said main frame and said wing portions for adjusting the position of said wing portions vertically.

3. In a grading machine, a main frame having ground engaging elements, a dozer blade, means. for adjusting the position of said dozer blade with respect to said main frame comprising first fluid pressure means acting between each end of said blade and said. main frame for determining the angular position of said blade with respect to said main frame, and second means for adjusting the position of said blade both laterally and longitudinally of said frame comprising a pair of fluid pressure motors each being connected to said blade at a point thereon different from the point of connection of said first fluid pressure means to said blade and each being connected to said main frame at a point spaced from the place of connection of the other, said pair of fluid pressure motors being selectively adjustable in length, and defining with said main frame a stable three-bar linkage for adjusting the position of said blade both laterally and longitudinally of said frame.

4. In a grading machine, a main frame having ground engaging elements, a frame mounted for tilting movement in a vertical plane with respect to said main frame, a grader blade having wing portions hingedly connected at their inner ends, means connected between each wing portion and said main frame for adjusting the position of the outer end of said wing portion in a horizontal plane, means connected between the inner end of each wing portion and said main frame for adjusting the position of the inner end of said Wing portion in a horizontal plane, the points of connection of said last named means to said main frame being spaced from each other so that a three bar linkage is defined with two of the links thereof being independently adjustable to shift said grader blade selectively in directions longitudinally and laterally thereof, a boom held rigidly to said tilting frame including a ground engaging element supported by said boom at a point thereon remote from said tilting frame, and means acting between said tilting frame and said wing portions for adjusting the position of said wing portions vertically.

5. The invention as defined in claim 4 wherein means are connected between said wing portion and said main frame for preventing turning of said wing portion about its longitudinal axis.

6. The invention as defined in claim 4 wherein said wing portions are connected to a center portion.

7. The invention as defined in claim 6 wherein said center portion is biased toward said wing portions.

8. In a grading machine, a main frame having ground engaging elements, a frame mounted for tilting movement in a vertical plane with respect to said main frame, a grader blade comprising wing portions and a center portion, means connecting the inner ends of said wing portions to said center portion, means for adjusting the inner and outer ends of said wing portions in a horizontal plane comprising an adjustable three bar linkage connected between the inner ends of said wing portions and said main frame, means connected between said wing portions and said main frame for adjusting the outer end of said wing portion, a boom held rigidly to said tilting frame including a ground engaging element supported by said boom at a point remote from said frame, and means acting between said tilting frame and said wing portions for adjusting the position of said grader blade vertically.

9. The invention as defined in claim 3 wherein means are connected between each wing portion and said main 7 frame for preventing turning of the wing portion about its longitudinal axis.

10. In a grading machine, a main frame having ground engaging elements, a dozer blade including wing portions hingedly connected adjacent their inner ends, means connected between a wing portion and said main frame for adjusting the position of the outer of said wing portion in a horizontal plane, means connected between the inner end of each wing portion and said main frame for selectively adjusting the position of the inner end of said wing portion in a horizontal plane, said last named means and the spacing of the connection of each to said main frame defining an independently adjustable three bar linkage, and means acting between said main frame and said wing portions for adjusting the position of said wing portions vertically.

11. The invention as defined in claim 10 wherein means are provided for preventing turning of said wing portion about its longitudinal axis.

12. The invention as defined in claim 10 wherein said wing portions are connected to a center portion.

13. The invention as defined in claim 12 wherein said center portion is biased toward said wing portions.

14. In a grading machine, a main frame having ground engaging elements, a dozer blade, means for adjusting the position of said dozer blade with respect to said main frame comprising first fluid pressure means acting between said blade and said main frame, and second means for adjusting the position of said blade both laterally and longitudinally of said frame comprising a pair of fluid pressure motors, each being connected to said blade at a. substantially common point thereon, and at a point spaced from the point of connection of said first fluid pressure means to said blade, said pair of fluid pressure motors being each connected to said main frame at a point on said main frame spaced from the point of connection of the other of said fluid pressure motors, said last named pair of fluid pressure motors defining with the portion of the frame therebetween an adjustable stable three-bar linkage.

References Cited in the file of this patent UNITED STATES PATENTS 1,997,001 Lamb Apr. 9, 1935 2,078,294 Stiehl et al. Apr. 27, 1937 2,502,681 Swanson Apr. 4, 1950 2,698,096 Hughes Dec. 28, 1954 2,698,491 Felt Jan. 4, 1955 2,730,823 Cassidy Jan. 17, 1956 2,891,334 Kinzer June 23, 1959 

